Traffic movement already is failing at the intersections, according to county standards, and is getting worse, county engineers said.

Widening Pine Ridge, or adding lanes at the intersections, would be almost impossible, requiring tens of millions in added spending to widen the interstate overpass as well as buy homes and businesses through eminent domain, said Jeff Perry, senior transportation planner with the engineering firm Stantec.

But by restructuring the intersections to use more efficient designs, the county could cut down on wait times at red lights and keep the crossings from bottlenecking, even as the population grows over the next 20 years, Perry said.

"It would actually help traffic more than if we just widened the lanes and would have the significant advantage that it doesn’t need new right-of-ways and bridges wouldn't have to be widened," he said.

The county plans to use a different design at each intersection.

At Pine Ridge and Livingston, the county will build a continuous flow intersection for about $6.6 million — about half as much as an overpass at the intersection, the county has estimated.

The intersection will save time by eliminating the left turn arrow on Livingston Road. Drivers turning left onto Pine Ridge will cross before the main intersection and stop at their own red light.

When Pine Ridge turns red and Livingston turns green, drivers turning left from each direction will go at the same time as drivers heading straight, rather than one before the other.

At Pine Ridge and I-75, a "divergent diamond" intersection would go one step further, getting rid of left turn arrows for all four directions. The lanes for eastbound and westbound traffic on Pine Ridge would cross each other just before the intersection and recross just after it.

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In this 2016 video, this video illustrates how the Continuous Flow intersection at Daniels Parkway/ Gunnery Road will operate.
Florida Department of Transportation

The intersection now has four separate signals, allowing left turns for eastbound and westbound traffic, then eastbound and westbound traffic, then left turns for northbound and southbound traffic, and finally northbound and southbound traffic.

But the new intersection would have just two separate signals — one that allows eastbound traffic to cross the lanes for westbound traffic, merge with drivers leaving the highway and recross the lanes for westbound traffic, and then one that does the opposite for westbound traffic.

The time delay caused by left turn arrows at traditional intersections adds up, Perry said.

"The problem is these intersections are in a two-minute cycle," he said. "But instead of 60 seconds for each direction, those left turns run for about 18 seconds in each direction. So they're stealing 30 percent of our movement capacity."

The divergent diamond would cost an estimated $8.8 million and be subject to FDOT approval.

At Pine Ridge and Whippoorwill, the county will ask the state to redesign the intersection at a cost of $4.8 million so Whippoorwill traffic will be allowed to make only right turns, then head along Pine Ridge until they can make a U-turn.

The plan at Whippoorwill is unpopular with nearby businesses and residents who want to keep their left turn.

Commissioner Penny Taylor cast the lone vote against the plan, saying more should have been done for those residents.

But the change is needed to keep traffic flowing, Commissioner Burt Saunders said.

"I understand the reluctance and know change is difficult, but if we don’t fix those intersections, we'll have a nightmare here," Saunders said.

All traffic in Naples is relative, said Rob Novotny, who has lived on Whippoorwill for 11 years and spent most of his life in New York.

"Traffic is a joke here," Novotny said. "It gets a little bad for three months.

"They're talking about spending how many millions so people will have to wait 60 seconds instead of 120 seconds?"

Commissioner Andy Solis likened the more efficient intersections to a new invention that's obvious in hindsight.

"It's like, how long did it take us to figure out that putting a suitcase on wheels was a good idea?" he said.

County staff will proceed with preliminary engineering, design and environmental assessments of the projects. There is no timetable yet for construction to begin.